diff --git a/lib/Sync.js b/lib/Sync.js
index 29ebed8a..71a6e7b9 100644
--- a/lib/Sync.js
+++ b/lib/Sync.js
@@ -83,8 +83,18 @@ Sync.prototype.storeTipBlock = function(b, allowReorgs, cb) {
     allowReorgs = true;
   }
   if (!b) return cb();
-
   var self = this;
+
+  if ( self.storingBlock ) {
+    console.log('## Storing a block already. Delaying storeTipBlock with:' +
+                b.hash);
+    return setTimeout( function() {
+      console.log('## Retrying storeTipBlock with: ' + b.hash);
+      self.storeTipBlock(b,allowReorgs,cb);
+    }, 1000);
+  }
+
+  self.storingBlock=1;
   var oldTip, oldNext, oldHeight, needReorg = false, height = -1;
   var newPrev = b.previousblockhash;
 
@@ -164,6 +174,7 @@ Sync.prototype.storeTipBlock = function(b, allowReorgs, cb) {
       if (err && err.toString().match(/WARN/)) {
         err = null;
       }
+      self.storingBlock=0;
       return cb(err, height);
     });
 };
@@ -177,7 +188,10 @@ Sync.prototype.processReorg = function(oldTip, oldNext, newPrev, oldHeight, cb)
 
       function(c) {
         self.bDb.getHeight(newPrev, function(err, height) {
-          if (!height) return c(new Error('Could not found block:' + newPrev));
+          if (!height) {
+            // Case 3 + allowReorgs = true
+            return c(new Error('Could not found block:' + newPrev));
+          }
           if (height<0) return c();
 
           newHeight = height + 1;